DNAzyme-based biosensing for food safety

Abstract Ensuring food safety is pivotal for public health and the stability of global food supply chains. Traditional detection methods, such as culture-based assays, polymerase chain reaction (PCR), and mass spectrometry, have demonstrated high sensitivity and specificity but are hindered by their high cost, operational complexity, and dependence on laboratory environment, making them unsuitable for rapid, on-site detection. DNAzyme-based biosensors offer a novel solution through their unique molecular recognition and catalytic properties, enabling sensitive, cost-effective, and portable detection. For instance, DNAzyme sensors targeting Escherichia coli have achieved detection limits as low as 10³ CFU/mL in food matrices like meat and juice, while colorimetric DNAzyme platforms for lead ion (Pb²⁺) detection have demonstrated sensitivity down to 1 nmol/L, making them suitable for on-site monitoring. This review systematically explores the applications of DNAzyme technology in detecting food contaminants, including pathogens, mycotoxins, heavy metals, antibiotics, and pesticide residues. This highlights the advantages of DNAzyme technology in terms of rapid detection, enhanced sensitivity, and strong anti-interference capability while critically analyzing the challenges encountered in real-world applications. Furthermore, this review proposes key directions for advancing DNAzyme commercialization and interdisciplinary integration, providing a foundation for future developments in food safety diagnostics.